Whereas exploitation of land-based oil and gas resources may have peaked, the opportunity to expand exploitation of oil and gas resources at offshore and deep water sites remains. This brings many challenges to the industry ranging from exploration to production. Amongst such challenges is the need to recover the produced resources in a consistent and reliable manner with minimal impact upon the environment.
Typically, the exploitation of a subsea field requires subsea deployment of equipment and establishment of a seabed infrastructure for delivery of product. Multiple wells may be established to exploit a reservoir, and these wells generally will be connected to floating production, storage and offloading (FPSO) units by conduits. These conduits may be bundled flowlines serving multiple purposes including production, annulus access and remote control of the wells. These flowlines may be at least partially buried in the seabed. Riser bundles to the FPSO may be installed in free catenaries.
Intervention may be required from time to time to inspect and maintain such subsea structures and systems. Whereas some subsea operations can be conducted by divers, taking account of the extreme depths of many sites, it is becoming more common to use remotely operated vehicles (ROVs) and tooling to perform the necessary tasks. Thus it may be necessary to undertake a subsea task at extreme depth in order to restore control of a subsea system, repair or replace worn or damaged components, override or bypass a failed component, or install sensors to monitor problem areas.